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Ferromagnetic GaMnAs containing up to 10% Mn has been grown by migration-enhanced epitaxy at a substrate temperature of 150 °C. The lattice constant of hypothetical zinc-blende structure MnAs is determined to be 5.90 Å, which deviates somewhat from previously reported values. This deviation is ascribed to growth-condition-dependent density of point defects. Magnetization measurements showed an onset of ferromagnetic ordering around 75 K for the GaMnAs layer with 10% Mn. This means that the trend of falling Curie temperatures with increasing Mn concentrations above 5.3% is broken.

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With the aim to follow the development of the electronic properties in thin films, angle-resolved photoelectron spectroscopy has been used to investigate molecular beam epitaxy grown InAs layers on GaAs(111)A and GaAs layers on AlAs͑100͒, lattice mismatch 7.2% and 0.1%, respectively. The results show that the bulk electronic structure in the overlayer material is established only in films thicker than 3-4 nm and that the interface region in effect displays alloylike electronic properties even though the interface is geometrically abrupt. Comparing computations of strain effects on the electronic structure in bulk InAs with the experimental data on the InAs cap layers, it was possible to separate the contributions of geometrical strain effects, extending 5-6 nm into the overlayer, and the electronic interface effects, extending 3-4 nm.

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